if (tags_only || heads_only) {
                int match;
 
-               match = heads_only && !prefixcmp(refname, "refs/heads/");
-               match |= tags_only && !prefixcmp(refname, "refs/tags/");
+               match = heads_only && starts_with(refname, "refs/heads/");
+               match |= tags_only && starts_with(refname, "refs/tags/");
                if (!match)
                        return 0;
        }
                while (*pattern) {
                        unsigned char sha1[20];
 
-                       if (!prefixcmp(*pattern, "refs/") &&
+                       if (starts_with(*pattern, "refs/") &&
                            !read_ref(*pattern, sha1)) {
                                if (!quiet)
                                        show_one(*pattern, sha1);